Multiple vulnerabilities in Cisco IOS XR Software for Cisco 8000 and Network Convergence System 540 Series Routers
| Risk | Low |
| Patch available | YES |
| Number of vulnerabilities | 2 |
| CVE-ID | CVE-2021-34708 CVE-2021-34709 |
| CWE-ID | CWE-347 |
| Exploitation vector | Local |
| Public exploit | N/A |
| Vulnerable software |
Cisco 8000 Series Routers Hardware solutions / Routers & switches, VoIP, GSM, etc Cisco Network Convergence System 540 Series Routers Hardware solutions / Routers & switches, VoIP, GSM, etc |
| Vendor | Cisco Systems, Inc |
Security Bulletin
This security bulletin contains information about 2 vulnerabilities.
1) Improper Verification of Cryptographic Signature
EUVDB-ID: #VU56424
Risk: Low
CVSSv4.0: 5.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]
CVE-ID: CVE-2021-34708
CWE-ID:
CWE-347 - Improper Verification of Cryptographic Signature
Exploit availability: No
DescriptionThe vulnerability allows a local administrator to execute arbitrary code on the system.
The vulnerability exists due to an unsigned script within the ISO that is not verified when the install request is being processed. A local administrator can modify an ISO image and execute arbitrary code on the affected device.
MitigationInstall updates from vendor's website.
Vulnerable software versionsCisco 8000 Series Routers: before 7.3.2
Cisco Network Convergence System 540 Series Routers: before 7.3.2
CPE2.3- cpe:2.3:h:cisco_systems:cisco_8000_series_routers:*:*:*:*:*:*:*:*
- cpe:2.3:h:cisco_systems:cisco_network_convergence_system_540_series_routers:*:*:*:*:*:*:*:*
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-lnt-QN9mCzwn
Q & A
Can this vulnerability be exploited remotely?
No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.
How the attacker can exploit this vulnerability?
The attacker would have to send a specially crafted request to the affected device in order to exploit this vulnerability.
The attacker would have to login to the system and perform certain actions in order to exploit this vulnerability.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.
2) Improper Verification of Cryptographic Signature
EUVDB-ID: #VU56425
Risk: Low
CVSSv4.0: 5.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]
CVE-ID: CVE-2021-34709
CWE-ID:
CWE-347 - Improper Verification of Cryptographic Signature
Exploit availability: No
DescriptionThe vulnerability allows a local administrator to execute arbitrary code on the system.
The vulnerability exists in the Cisco IOS XR due to a race condition that occurs when the install request is being processed. A local administrator can modify an ISO image and execute arbitrary code on the affected device.
MitigationInstall updates from vendor's website.
Vulnerable software versionsCisco 8000 Series Routers: before 7.3.2
Cisco Network Convergence System 540 Series Routers: before 7.3.2
CPE2.3- cpe:2.3:h:cisco_systems:cisco_8000_series_routers:*:*:*:*:*:*:*:*
- cpe:2.3:h:cisco_systems:cisco_network_convergence_system_540_series_routers:*:*:*:*:*:*:*:*
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-lnt-QN9mCzwn
Q & A
Can this vulnerability be exploited remotely?
No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.
How the attacker can exploit this vulnerability?
The attacker would have to send a specially crafted request to the affected device in order to exploit this vulnerability.
The attacker would have to login to the system and perform certain actions in order to exploit this vulnerability.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.
